Hydraulic control arrangement for a pipe relining machine

ABSTRACT

An hydraulic control arrangement ( 66 ) in association with a pipe relining machine Includes fluid pressure supply and return lines ( 32, 33 ), a motor controller ( 80 ) to control a motor ( 67 ) and a radial position controller. The radial position controller supplies fluid under pressure to a radial positioning arrangement ( 46 ) to set diameter of a relined pipe. The radial position controller has a first normally closed valve ( 83 ) supplying fluid under pressure to the radial positioning arrangement ( 46 ) and a second normally open valve ( 84 ) allowing fluid to be withdrawn from the radial positioning arrangement ( 46 ). The arrangement ( 66 ) allows the pipe relining machine to be withdrawn in the event of a failure.

FIELD OF INVENTION

[0001] This invention relates to a system for the relining of pipesparticularly underground pipes and particularly to arrangements by whicha pipe relining machine operating underground can be operated andcontrolled from above ground.

BACKGROUND OF THE INVENTION

[0002] In pipe relining processes a continuous strip of plastic materialis laid in spiral fashion in the inside of a pipe and joined alonglongitudinal edges to provide a new surface for fluids such a sewage orwater to flow through. Operation of a pipe relining device used in thepipe is necessarily from a remote location and it is the object of thisinvention to provide a system for hydraulic control of such as piperelining device from a remote location and to provide a fail safeoperation system.

[0003] When operating a pipe relining device it is necessary to have apower supply and control arrangement to correctly operate and controlthe relining device. It is also often necessary to get the control andoperation unit to difficult places on a site and it is a further objectof this invention to provide an arrangement by which such objects can beachieved.

BRIEF DESCRIPTION OF THE INVENTION

[0004] In one form therefore although this may not necessarily be theonly or broadest form the invention is said to reside in an hydrauliccontrol arrangement for a pipe relining machine, the hydraulic controlarrangement including a fluid pressure supply line and a fluid returnline to a fluid storage tank, a motor controller to control a motorsupplied by the fluid pressure supply line, and a radial positioncontroller, the radial position controller supplying fluid underpressure to a radial positioning arrangement to set diameter of arelined pipe, the radial position controller having a first normallyclosed valve supplying fluid under pressure to the radial positioningarrangement and a second normally open valve allowing fluid to bewithdrawn from the radial positioning arrangement.

[0005] Preferably the fluid withdrawn from the radial positioningarrangement is drained to a drain tank.

[0006] The pipe relining machine according to one constructionalembodiment and in which the hydraulic control circuit of the presentinvention may be used may have a fixed portion and a rotating portion.Within the fixed portion there may be electrical and hydraulic fluidconnections which are supplied from the remote control position fromabove ground or outside the pipe. A rotary union may then be used totransfer hydraulic fluid and electric control and feedback signals toand from the various operating components within the rotating portion.Within the rotating portion there may be an electrical solenoidcontrolled hydraulic fluid control block which is remotely controllablefrom above ground or outside the pipe.

[0007] It may be noted that the radial positioning arrangement may benormally operated at a pressure that is lower than the pressure in thefluid pressure supply line and the fluid return line and hence it is notpossible to drain the fluid from the radial positioning arrangement backto the storage tank. The drain tank which is preferably within therotating portion is used for this purpose.

[0008] If hydraulic pressure is lost to the relining device orelectrical control power is lost then there is a danger that therelining device could be jammed in the pipe and an excavation may benecessary to remove it. Hence a fail safe system is provided accordingto the invention. The fail safe device is provided by the secondnormally open valve allowing fluid to be withdrawn from the radialpositioning arrangement. If electrical power is lost then the secondnormally open valve will open allowing hydraulic fluid to drain to thedrain tank thereby allowing the radial positioning device to relax itspressure against the previous turn of the pipe or the wall of the pipeto allow the relining device to be withdrawn. Similarly if hydraulicpressure is lost, perhaps by a ruptured hydraulic line or the like thenelectrical power to the second normally open valve can be removedallowing fluid to be withdrawn from the radial positioning arrangementso that the relining device can be withdrawn.

[0009] The radial positioning arrangement may have spring return of itshydraulic actuators to assist with draining of fluid from the actuatorsin the event of a failure or when it is necessary to remove the reliningdevice.

[0010] There may be a pressure transducer associated with the radialpositioning arrangement to observe the fluid pressure within the radialpositioning arrangement and to allow remote manual or automatic controlof the radial positioning arrangement.

[0011] In constant size operation when the radial positioningarrangement is held at a constant pressure, this pressure determines howhard out against the host pipe the new pipe being formed will be. Thepressure is kept at a sufficiently high value to force the liner or pipebeing formed out hard against the host or original pipe so that amaximum diameter pipe is formed. The pressure should not be so high asto cause the pipe relining device to stall. Typically in a segmentedsewer pipe or a PVC pipe each segment will have a slightly varying sizedue to manufacturing tolerances, damage to the pipe or build up of solidmaterial on the inside of the pipe. The pressure transducer allows theoperator or automatic control system to maintain the pressure at aconstant level when these changes in diameter are encountered. If thepressure is reduced to below a nominal level, caused by friction of theseals for instance, the radial positioning arrangement and hence therollers forming the relined pipe will retract under the action of thespring and the diameter of the pipe being formed will reduce. If thishappens too fast the plastic strip cannot reduce its size quick enoughand the strip being laid does not engage with the previous strip. At anintermediate setting an operator or automatic controller can bleedhydraulic fluid from the radial positioning arrangement using the secondnormally open valve at such a rate that the diameter of the pipe beingformed is reduced while still ensuring that the strip being laid engageswith the previous strip. This allows the wound pipe size to reduce indiameter at a controlled rate whilst the turns still remain locked tothe previous turn.

[0012] Further hydraulic control may be provided within the hydrauliccontrol circuit of the present invention for a lateral marking tool tomark branch pipes when relining a pipe and an auxiliary hydraulic supplymay be provided to operate devices such as strip cutters or lateralbranch opening tools.

[0013] In an alternative form the invention may be said to reside in apipe relining machine including an hydraulic control circuit, therelining machine having a non-rotating portion, a rotary union and arotating portion, the non-rotating portion having an electrical andhydraulic connections which are supplied from a remote control positionfrom above ground or outside the pipe, the rotary union being totransfer hydraulic fluid and electric control and feedback signals toand from various operating components within the rotating portion fromthe non-rotating portion, the rotating portion having electricalsolenoid controlled hydraulic control block which is remotelycontrollable from above ground or outside the pipe, the hydrauliccontrol circuit including a fluid pressure supply line and a fluidreturn line to a fluid storage tank, a motor controller to control amotor supplied by the fluid pressure supply line, and a radial positioncontrollers the radial position controller supplying fluid underpressure to a radial positioning arrangement to set the diameter of therelined pipe, the radial position controller having a first normallyclosed valve supplying fluid under pressure to the radial positioningarrangement and a second normally open valve allowing fluid to bewithdrawn from the radial positioning arrangement.

[0014] Preferably the feedback is by means of observation of thehydraulic pressure of an hydraulic fluid supplying the radialpositioning arrangement. The control of the diameter may be manual orautomatic.

[0015] In an alternative form the invention is said to reside in aremote control circuit for a pipe relining machine, the pipe reliningmachine including a fluid pressure supply line and a fluid return lineto a fluid storage tank, a motor to supply relining strip to the piperelining machine and a motor controller to control the motor supplied bythe fluid pressure supply line and a radial position controller, theradial position controller supplying fluid under pressure to a radialpositioning arrangement to set the diameter of the relined pipe, theremote control circuit including means to observe the hydraulic pressurein the radial positioning arrangement enabling the force being appliedto a previously laid strip to be observed and controlled whereby thediameter of the relined pipe may be varied or held the same.

[0016] The means to observe the hydraulic pressure in the radialpositioning arrangement may be a pressure transducer.

[0017] Preferably the radial position controller has a first normallydosed valve supplying fluid under pressure to the radial positioningarrangement and a second normally open valve allowing fluid to bewithdrawn from the radial positioning arrangement, the fluid withdrawnfrom the radial positioning arrangement being drained to a drain tank.By this means if power to the pipe relining machine is lost the secondnormally open valve will open thus allowing fluid to be withdrawn fromthe radial positioning arrangement so that the diameter is reduced andhence relining device can be withdrawn.

[0018] In a further form the invention is said to reside in a selfpropelled power and control unit for a remote operation device, the unithaving a motor, drive means for the unit driven by the motor, a powergeneration arrangement driven by the motor, a cable drum to hold a powersupply and control cable, the cable drum adapted to be driven by themotor to unwind and wind the cable and a control arrangement on the unitwhereby an operator can observe and control the operation of the remoteoperation device.

[0019] It will be seen that by this form of the invention the powersupply and control unit is self propelled by its motor so that it can bedriven by an operator to a work site and it has on it the necessarypower supply and control functions to enable the remote operation devicesuch as a pipe relining device to be operated.

[0020] The power generation arrangement may be electrical power,hydraulic power or both electric and hydraulic. The necessary tanks forhydraulic power supply and oil intercoolers and the like may be providedon the power supply and control unit.

[0021] The drive means may be by use of direct drive from the motor orby hydraulic drive or electric drive and may include wheels or tracksand may be operated on the skid steer system. The drive means may beadapted to be reduced in width so that the power supply and control unitcan be driven into or through tight situations or to be widened to givebetter stability during use.

[0022] The cable drum may be driven electrically or hydraulically andmay include a clutch arrangement to provide a constant tension on thepower supply and control cable to wind the cable as the remote operationdevice is moved. There may be provided slip rings associated with thecable drum for transfer of the necessary hydraulic power and controlcables from the unit to the cable.

[0023] As discussed above in one form of the invention the remoteoperation device may be a pipe relining device. The remote operationdevice may also be other devices associated with pipe relining. Thesemay include video inspection devices which can be driven by powersupplied from the power and control unit and carry a video camera whichcan be viewed by the control arrangement. Alternatively it may be acleaner unit, lateral cutter or other device. The various items may beconnected to the power supply and control cable as required.

[0024] The self propelled power and control unit according to thisinvention may also include a jib crane and winch arrangement whichenables a remote operation device to be retrieved and transported asrequired.

[0025] The remote operation device according to this invention mayinclude an operator's seat so that an operator can actually sit on theunit to drive the unit to the necessary work site and from that positionobserve the various control devices and operate the remote operationdevices as required. The control arrangement may include video screensfor remote observation of action of the remote operation device as wellas control panels and necessary computer systems.

[0026] It will be seen generally, therefore, that a self propelleddevice is provided according to this invention with the necessaryarrangements for control and power supply for a remote operation device.

BRIEF DESCRIPTION OF THE DRAWINGS

[0027] This then generally describes the invention but to assist withunderstanding reference will now be made to the accompanying drawingswhich show a preferred embodiment of the invention.

[0028] In the drawings:

[0029]FIG. 1 shows a schematic arrangement of one embodiment of a piperelining device including an hydraulic control system according to thepresent invention;

[0030]FIG. 2 shows one embodiment of the underground portion of a piperelining device including an hydraulic control system according to thepresent invention;

[0031]FIG. 3 shows a schematic hydraulic circuit for the embodimentshown in FIG. 2.

[0032]FIG. 4 shows in detail the hydraulic circuit according to oneembodiment of FIG. 2;

[0033]FIG. 5 shows an embodiment of a radial positioning arrangementoperated hydraulically according to one embodiment of the invention;

[0034]FIG. 6 shows a front prospective view of a self propelled powerand control unit being the above ground portion according to the presentinvention;

[0035]FIG. 7 shows a rear view of the unit shown in FIG. 6; and

[0036]FIG. 8 shows a side view of the unit shown in FIG. 6.

DETAIL DESCRIPTION OF PREFERRED EMBODIMENTS

[0037] Now looking more closely to the drawings and in particular FIG. 1it will be seen that the pipe relining arrangement according to theinvention has an above ground portion being the portion enclosed withinthe dotted line 1 and a below ground portion being the portion enclosedwithin the dotted line 2. Between them are an electrical control signalcable 3 and hydraulic supply 5 and return 6 lines.

[0038] The above ground portion being the portion enclosed with in thedotted line 1 will be discussed in detail with respect to FIGS. 6 to 8but in general includes a control panel 10 and a display 11. Hydraulicfluid reservoir 12 supplies hydraulic pump 12 and pressurised fluid toaccumulator 13 for supply along hydraulic supply line 5. Hydraulicreturn 6 line returns hydraulic fluid to the tank 12.

[0039] The below ground portion being the portion enclosed within thedotted line 2 will be generally discussed with reference to FIGS. 2 to5. In general it includes a fixed portion 20, a rotating portion 21 anda relining strip placement head 23.

[0040] Now looking more closely at FIG. 2 it will be seen that theunderground portion of one embodiment of the invention of the piperelining device includes a forward section generally shown as 31 whichhas hydraulic fluid inlet 32 and a hydraulic fluid outlet 33. Anelectrical connection arrangement 34 is also used. The forward portion31 has forward shining lights 36 and a front or first video camera 37.

[0041] In this embodiment of a pipe relining tool the front portion 31does not rotate while a rotation portion generally shown as 40 rotatesas relining occurs and hence a rotary union 39 is provided between theforward section 31 and the rotating portion 40. The rotary union hasrotating connections for the hydraulic inlet and outlet lines as will bediscussed later as well as rotating electrical connections forelectrical devices in the rotating section 40 as required.

[0042] The rotating portion 38 of the rotary union 39 houses thehydraulic control circuitry according to the invention.

[0043] In the rotating portion 40 a rear drive 42 includes an hydraulicmotor to feed relining strip (not shown) to reline the pipe in a systemof a type as discussed in PCT Publication WO00/17564

[0044] In the process of spiral relining of a pipe from within therelining strip material is forced against a previous spiral of reliningstrip material and joined to it with a male and female type ofconnection by means of rollers 44 on support arms 45 supported on aradial positioning arrangement 46 at each end. The radial positioningarrangement 46 provides a radial pressure to ensure the pipe relining isapplied firmly against the previous spiral of relining strip or againstthe wall of the pipe being relined. In this embodiment as particularlyshown in FIG. 5 the radial positioning arrangement 46 has four radialarms 45 at each end but more or less could be provided depending uponthe space available or the nominal diameter of the pipe being relined.Each arm 45 may have a radially extending hydraulic actuator or theremay be a single actuator at each end providing radial pressure by aseries of levers or gears. A spring arrangement (not shown) is providedto retract the arms 55.

[0045] In this illustration shown in FIG. 5 several of the rollers havebeen omitted so that the region of the rotating device 40 within therollers can be observed.

[0046] Mounted to the central tube 48 of the rotating device is alateral marking device 50. A second video camera 52 observes the regionof a lateral pipe extending from the pipe being relined where therelining material is being applied and after the relining material hasbeen applied the lateral marker 50 can be operated when it is observedto be at the region of the lateral branch pipe to mark the reliningmaterial so that subsequently an opening can be cut at that spot.

[0047] The radial positioning arrangement 16 as shown in detail in FIG.5 has the central tube 48 of the rotating portion of the relining devicewith radial arms 45 extending from each end. In each radial arm is anhydraulic actuator 55 upon the ends of longitudinally adjacent pairs ofwhich are supported the rollers 44 which bear against the walls of thepipe being relined. Springs (not shown) in each arm 45 are adapted toretract the hydraulic actuator 55 in the event of lack of hydraulicpower.

[0048] One embodiment of an hydraulic control circuit according to thepresent invention is shown in FIGS. 3 and 4.

[0049]FIG. 3 shows a schematic electrical and hydraulic circuitaccording to one embodiment of the invention. In this embodimentpressurised hydraulic fluid supply line 32 and a return line 32 feedinto in the non-rotating portion 38 of the rotary union 39 andelectrical control and monitoring lines 60 supplied through cable 3(FIG. 1) feed into the non-rotating portion 62 of the electrical rotaryunion 61. Some electrical control and monitoring lines 64 remain in thenon-rotating portion of the rotary union 62 to go to electrical devicessuch as the first video camera and associated lights. Other electricalcontrol lines 65 extend from the rotating portion 63 of the electricalrotary union 61.

[0050] Hydraulic lines extend from the non-rotating portion 28 of thehydraulic rotary union 39 into the rotating portion 38 of the rotaryunion and into a control block 66. Within the control block is a seriesof electrically actuated valves for the various functions of therelining device as will be discussed with reference to FIG. 4.Pressurised fluid is supplied to a motor 67. Hydraulic fluid is alsosupplied to the radial positioning arrangement 46, to the lateralspotter or marking device 50 as discussed above and to an auxiliarysupply 68 for other hydraulically actuated tools and devices asrequired. Pressure transducer 70 observes the pressure applied to theradial positioning arrangement 46.

[0051] Electrical control and monitoring lines 65 extend from therotating portion 63 of the rotary union 61 to a splitter box 72 fromwhich some electrical lines 73 go to the control block 66 to operate theelectrical solenoids and electrical lines 74 go to other electricaldevices such as the second video camera 52 and associated lights (FIG.2) and the pressure transducer 70.

[0052] The hydraulic control circuit shown in detail in FIG. 4 has apressurised hydraulic fluid supply line 32 and a return line 33 feedinginto a control block 66. Within the control block 66 is a series ofelectrically actuated valves for the various functions of the reliningdevice. A motor control valve 80 provides pressurised fluid to the motor67 when actuated. The valve 80 allows the motor to be driven in eitherdirection so that relining strip material can be laid and unlaid.Hydraulic fluid is also supplied through valve 81 to the lateral spotteror marking device 50 as discussed above and through valve 82 for theauxiliary supply 68 for other hydraulically actuated tools and devicesas required.

[0053] The hydraulic control circuit also provides pressurised hydraulicfluid to the radial positioning arrangement 46. Valve 83 which isnormally closed is actuated to supply hydraulic fluid to the radialpositioning arrangement 46 and valve 84, which is normally open when notactuated and dosed when actuated, prevents hydraulic fluid draining inline 85 to drain tank 86 during normal operation of the device. Apressure transducer 70 enables the hydraulic fluid pressure supply tothe radial positioning arrangement 46 to be monitored remotely andadjusted as required. Automatic monitoring and adjustment may also beused.

[0054] As discussed above if hydraulic pressure is lost to the reliningdevice or electrical control power is lost then there is a danger thatthe relining device could be jammed in the pipe and an excavation may benecessary to remove it and hence a fail safe system is providedaccording to the invention. The fail safe device is provided by thevalve 84 allowing fluid to be withdrawn from the radial positioningarrangement 46. If electrical power is lost then the valve 84 will openallowing hydraulic fluid to drain to the drain tank 86 thereby allowingthe radial positioning device 46 to relax its pressure against the wallof the pipe to allow the relining device to be withdrawn. Similarly ifhydraulic pressure is lost, perhaps by a ruptured hydraulic line or thelike then power to the valve 84 can be deactivated allowing fluid to bewithdrawn from the radial positioning arrangement 46 to the tank 86 sothat the relining device can be withdrawn.

[0055] Now looking more closely at FIGS. 6 to 8 one embodiment of anabove ground remote control and power supply arrangement for the piperelining device will be discussed. This embodiment is a self propelledunit but a static unit such as could be transported on the back of atruck is also within the scope of the invention.

[0056] In FIG. 6 it will be seen that the above ground remote controland power supply arrangement comprises a body 102 which is supported ontracks 103. Within the body and not shown is a motor and powergeneration system including an hydraulic pump (item 13 in FIG. 1) andelectrical generators. The tracks may be driven hydraulically and mayinclude arrangements for moving the tracks wider for better stability.On the body is an operator's seat 105 and a drive panel 107 with thenecessary controls 108 for driving the unit.

[0057] A forward frame 110 and a rearward frame 112 mounted to the body102 support a jib crane 114. On the jib crane is a winch 116 whichdrives a crane cable and hook 118.

[0058] Supported on the rear frame 112 is an oil cooler 120 for thehydraulic pump. The oil cooler is omitted in FIG. 7 for clarity.

[0059] Supported on the forward frame 110 is a pair of video screens122. An operator sitting on the seat 105 can observe the video screens122 to follow what is occurring remotely at the underground portion ofthe pipe relining device via video cameras 37 and 52 (FIG. 2). A controlpanel 124 is also supported on the front frame 110 which enables theoperator to observe readings from functions of the underground portionof the pipe relining device and to control the underground portion ofthe pipe relining device accordingly.

[0060] Mounted to the front of the self propelled power and control unitis a cable drum 130 upon which is rolled a power supply and controlcable 132. The cable drum is driven by a motor 134 through chain 136within chain housing 138.

[0061] On the left hand side of the cable drum are electrical slip ringarrangements 140 by which electrical control for the remote operationdevice is transferred to the control cable 132 and on the right handdevice are hydraulic slip rings 142 by which hydraulic power for theunderground portion of the pipe relining device is provided to the cabledrum.

[0062] Although a combined power and control cable is shown in thisembodiment wound onto a single cable drum in an alternative embodimentthere may be separate control cables and power supply cables. The powersupply cables may be hydraulic power or electrical power cables.

[0063] The unit according to this invention may also include a dozerblade 146 which can be used to dear a work area where necessary and whenbearing against the ground can provide stability during operation of thecrane.

[0064] It will be seen that by this arrangement there is provided a selfpropelled unit which can be driven by an operator to a work site and allof the necessary functions for operation of a remote operation devicesuch as a pipe reliner are provided on the unit.

[0065] Throughout this specification various indications have been givenas to the scope of the invention but the invention is not limited to anyone of these but may reside in two or more of these combined together.The examples are given for illustration only and not for limitation.

1. An hydraulic control arrangement for a pipe relining machine, thehydraulic control arrangement including a fluid pressure supply line anda fluid return line to a fluid storage tank, a motor controller tocontrol a motor supplied by the fluid pressure supply line, and a radialposition controller, the radial position controller supplying fluidunder pressure to a radial positioning arrangement to set diameter of arelined pipe, the radial position controller having a first normallyclosed valve supplying fluid under pressure to the radial positioningarrangement and a second normally open valve allowing fluid to bewithdrawn from the radial positioning arrangement.
 2. An hydrauliccontrol circuit as in claim 1 wherein the radial positioning arrangementhas spring return to assist with draining of fluid from the radialpositioning arrangement in the event of a failure or when it isnecessary to remove the relining machine.
 3. An hydraulic controlcircuit as in claim 1 further including a pressure transducer associatedwith the radial positioning arrangement to observe the fluid pressurewithin the radial positioning arrangement and to allow remote manual orautomatic control of the radial positioning arrangement.
 4. An hydrauliccontrol circuit as in claim 1 wherein the fluid withdrawn from theradial positioning arrangement is drained to a drain tank.
 5. A piperelining machine including an hydraulic control circuit, the reliningmachine having a non-rotating portion, a rotary union and a rotatingportion, the non-rotating portion having an electrical and hydraulicconnections which are supplied from a remote control position from aboveground or outside the pipe, the rotary union being to transfer hydraulicfluid and electric control and feedback signals to and from variousoperating components within the rotating portion from the non-rotatingportion, the rotating portion having electrical solenoid controlledhydraulic control block which is remotely controllable from above groundor outside the pipe, the hydraulic control circuit including a fluidpressure supply line and a fluid return line to a fluid storage tank, amotor controller to control a motor supplied by the fluid pressuresupply line, and a radial position controller, the radial positioncontroller supplying fluid under pressure to a radial positioningarrangement to set the diameter of the relined pipe, the radial positioncontroller having a first normally dosed valve supplying fluid underpressure to the radial positioning arrangement and a second normallyopen valve allowing fluid to be withdrawn from the radial positioningarrangement.
 6. A pipe relining machine as in claim 5 wherein the fluidwithdrawn from the radial positioning arrangement is drained to a draintank.
 7. A pipe relining machine as in claim 5 wherein the radialpositioning arrangement has spring return to assist with draining offluid from the radial positioning arrangement in the event of a failureor when it is necessary to remove the relining machine.
 8. A piperelining machine as in claim 5 further including a pressure transducerassociated with the radial positioning arrangement to observe the fluidpressure within the radial positioning arrangement and to allow remotemanual or automatic control of the radial positioning arrangement.
 9. Apipe relining machine as in claim 5 further including a lateral markingtool to mark branch pipes when relining a pipe.
 10. A pipe reliningmachine as in claim 5 wherein the hydraulic control circuit includes apower and control unit for the pipe relining machine, the unit having amotor, drive means for the unit driven by the motor, a power generationarrangement driven by the motor, a cable drum to hold a power supply andcontrol cable, the cable drum adapted to be driven by the motor tounwind and wind the cable and a control arrangement on the unit wherebyan operator can observe and control the operation of the pipe reliningmachine;
 11. A pipe relining machine as in claim 4 further including afeedback arrangement enabling the radial position of the radialpositioning arrangement to be observed and controlled whereby thediameter of the relined pipe may be varied or held the same.
 12. A piperelining arrangement including a remote control system and a piperelining machine; the remote control system including a power andcontrol unit for the pipe relining machine, the unit having a motor,drive means for the unit driven by the motor, a power generationarrangement driven by the motor, a cable drum to hold a power supply andcontrol cable, the cable drum adapted to be driven by the motor tounwind and wind the cable and a control arrangement on the unit wherebyan operator can observe and control the operation of the pipe reliningmachine; the pipe relining machine having a motor to supply reliningstrip to the pipe relining machine and a radial positioning arrangement,the radial positioning arrangement being adapted to form the diameter ofthe relined pipe; the remote control system having a feedbackarrangement enabling the radial position of the radial positioningarrangement to be observed and controlled whereby the diameter of therelined pipe may be varied or held the same.
 13. A pipe reliningarrangement as in claim 12 wherein the feedback is by means ofobservation of the hydraulic pressure of an hydraulic fluid supplyingthe radial positioning arrangement. The control of the diameter may bemanual or automatic.
 14. A pipe relining arrangement as in claim 12wherein the remote control system is a self propelled power and controlunit.
 15. A pipe relining arrangement as in claim 12 wherein the radialpositioning arrangement includes a radial position controller, theradial position controller supplying fluid under pressure to the radialpositioning arrangement to set diameter of a relined pipe, the radialposition controller having a first normally closed valve supplying fluidunder pressure to the radial positioning arrangement and a secondnormally open valve allowing fluid to be withdrawn from the radialpositioning arrangement.
 16. A pipe relining arrangement as in claim 15wherein the fluid withdrawn from the radial positioning arrangement isgdrained to a drain tank.
 17. A pipe relining arrangement as in claim 14wherein the radial positioning arrangement has spring return to assistwith draining of fluid from the radial positioning arrangement in theevent of a failure or when it is necessary to remove the reliningdevice.
 18. A pipe relining arrangement as in claim 14 further includinga pressure transducer associated with the radial positioning arrangementto observe the fluid pressure within the radial positioning arrangementand to allow remote manual or automatic control of the radialpositioning arrangement.
 19. A remote control circuit for a piperelining machine, the pipe relining machine including a fluid pressuresupply line and a fluid return line to a fluid storage tank, a motor tosupply relining strip to the pipe relining machine and a motorcontroller to control the motor supplied by the fluid pressure supplyline and a radial position controller, the radial position controllersupplying fluid under pressure to a radial positioning arrangement toset the diameter of the relined pipe, the remote control circuitincluding means to observe the hydraulic pressure in the radialpositioning arrangement enabling the force being applied to a previouslylaid strip to be observed and controlled whereby the diameter of therelined pipe may be varied or held the same.
 20. A remote controlcircuit as in claim 19 wherein the means to observe the hydraulicpressure in the radial positioning arrangement is a pressure transducer.21. A remote control circuit as in claim 19 wherein the radial positioncontroller has a first normally closed valve supplying fluid underpressure to the radial positioning arrangement and a second normallyopen valve allowing fluid to be withdrawn from the radial positioningarrangement.
 22. A remote control circuit as in claim 19 wherein thefluid withdrawn from the radial positioning arrangement is drained to adrain tank.
 23. A self propelled power and control unit for a remoteoperation device, the unit having a motor, drive means for the unitdriven by the motor, a power generation arrangement driven by the motor,a cable drum to hold a power supply and control cable, the cable drumadapted to be driven by the motor to unwind and wind the cable and acontrol arrangement on the unit whereby an operator can observe andcontrol the operation of the remote operation device.
 24. A selfpropelled power and control unit as in claim 23 wherein the powergeneration arrangement is selected from electrical power, hydraulicpower or both electric and hydraulic.
 25. A self propelled power andcontrol unit as in claim 23 wherein the drive means is by direct drivefrom the motor or by hydraulic drive or electric drive and the drivemeans include wheels or tracks and may be operated on the skid steersystem.
 26. A self propelled power and control unit as in claim 23wherein the drive means is adapted to be reduced in width so that thepower supply and control unit can be driven into or through tightsituations.
 27. A self propelled power and control unit as in claim 23wherein the cable drum is electrically or hydraulically driven andincludes a clutch arrangement to provide a constant tension on the powersupply and control cable to wind the cable as the remote operationdevice is moved.
 28. A self propelled power and control unit as in claim23 further including slip rings associated with the cable drum fortransfer of the power and control cables from the unit to the cable. 29.A self propelled power and control unit as in claim 23 further includinga jib crane and winch arrangement which enables a remote operationdevice to be retrieved and transported as required.
 30. A self propelledpower and control unit as in claim 23 further including an operator'sseat so that an operator can sit on the unit to drive the unit to thenecessary work site and from that position observe the various controldevices and operate the remote operation device as required.
 31. A selfpropelled power and control unit as in claim 23 further includingcontrol panels, computer systems and video screens for remoteobservation of action of the remote operation device.
 32. A selfpropelled power and control unit as in claim 23 wherein the remoteoperation device is a pipe relining machine.